1. Field of the Invention
The present invention is directed to the field of an escape for a building, more particularly, relates to an escape installed in a building to let a person escape to a place of safety when a fire or an earthquake is occurred.
2. Description of the Prior Art
A building is provided with an escape in order to let a person escape from the inside of the building to a place of safety when a fire or an earthquake is occurred. The escape must be constructed to facilitate a person's escaping from a dangerous place in case of emergency. Therefore, as a general rule, the escape of the building must have a construction that a people can escape from any storeys of the building rapidly and safely. Furthermore, the escape is usually installed in an isolated space, such as in a fire zone or on an external wall of the building, in order to eliminate the influence of flame or smoke.
An emergency staircase is broadly used as an escape installed in the inside of a building. However, the emergency staircase is installed in a vertical hole formed in the building and therefore, the installation of an emergency staircase means to form a chimney-like hole in the building. Thereby, in case that flame of smoke flows into the chimney-like hole, it would be difficult for a person to pass the emergency staircase in the hole.
In order to avoid the influence of smoke of a fire, it is a usual manner to install an emergency staircase on an external wall of a building as shown in FIG. 12. In the figure, an emergency staircase 93 having a platform 91 and a stairs 92 is attached to an external wall 2 of a building 1 and so, in emergency, a people can escape from the building 1 through an emergency door 20 and the staircase 93.
However, an emergency staircase occupies a space in the inside or outside of a building though an emergency staircase will be used scarcely. That is to say, it would be desirable to eliminate the space occupied by the emergency staircase in a building.